What accounts for London's explosive growth in the 19th and early 20th centuries? Tim Phillips talks to Stephen Redding of Princeton University about new research that shows how important the railways have been, and continue to be, in creating the modern metropolis.

Over the last two centuries, transportation innovations have drastically changed urban landscapes. This column explores how the mid-19th century transport revolution shaped the urban agglomeration of London. The results show Greater London’s population would have been 30% lower in 1921 without the railway network. The findings and the quantitative urban models employed highlight the role of modern transport technologies in sustaining dense concentrations of economic activity.

In Japan, as in many other countries, manufacturers are testing automated driving technology, and policymakers are considering how to implement it. This column discusses the demand for the technology in Japan, using a survey of consumers. Almost half intended to purchase automated vehicles or driving systems, but willingness to pay was below the likely additional cost.

The consensus among economic (but not maritime) historians that maritime technology was more or less stagnant for 300 years until iron steamships appeared in the mid-19th century is largely based on indirect measures, such as changes in the cost of shipping freight or the length of voyages. This column instead looks directly at how the speed of ships in different winds improved over time. The speed of British ships rose by around half between 1750 and 1830 (albeit from a low base) thanks to innovations like the copper plating of hulls and the move from wooden to iron joints and bolts.

Driverless vehicles are expected to become a reality on our roads in the near future. This column reviews research into the effects this will have on the economy and on society. New business models for truck operators and delivery companies, commuters putting the time they would have been driving to more productive use, and fewer accidents and greater efficiency on the road are among the developments that will benefit the economy. At the same time, driverless cars will become a major means of transport for elderly people in rural areas, while in urban areas the number of cars owned for personal use will drop sharply.

The motor vehicle was very quick to replace horses in the early 20th century, and the advent of the electric car suggests that another profound shift in transportation and energy could be around the corner. This column projects how different rates of electric car adoption will effect oil demand and consumption over the next three decades. In a fast-adoption scenario, oil prices could converge to the level of current coal prices by the early 2040s. Even under a slow adoption scenario, oil could become obsolete before it is depleted.

The population sizes of cities are highly indicative of their industrial structure. This column identifies the cities in Japan in which manufacturing industries have significant agglomeration, and reveals that the number of these agglomeration cities differs widely across industries, with industries that are located in a smaller number of cities being found in larger cities. There is also considerable churning of population and industrial activities among Japanese cities, with population growth reflecting the development of highway and high-speed railway networks.

Transport infrastructure investment is a cornerstone of growth-promoting strategies around the world. However, investment in new infrastructure is not always conducive to stronger economic performance. This column argues that the lack of positive economic returns may be due to institutional failures mitigating the growth effects of public capital expenditures. In contexts marked by weak and inefficient governments and widespread corruption, different types of road investments yield low or no economic returns.

Trains use three times less energy than cars to transport people; six times less energy than trucks to move freight. Trains use and emit just one-fifth the amount of carbon dioxide. Governments can help fight global warming by using competition policy and tax incentives to induce transportation customers to switch to rail.